My caterpillar isn't moving. It hasn't moved in a long time. Is it dead? I put it back on a leaf but it won't eat. Did I do something wrong?
- No, your didn't do anything wrong BUT what you do need to do is leave the caterpillar alone! The caterpillar is probably getting ready to molt (shed its skin). When getting ready to molt, larva stop eating and should not be disturbed. See the section on molting.
There is this long string thing hanging from my Monarch chrysalis. What is it?
- That string thing indicates that your Monarch caterpillar was a victim of a Tachinid Fly.
How long does a butterfly live?
- Most adult butterflies only live for around two weeks. Monarchs can live a longer depending upon the time of the year and whether or not they are in diapause (overwintering). Monarchs overwinter as adult butterflies, not as pupae, larvae, or eggs.
How can I tell if my Monarch is a boy or a girl?
- Check out the Gender ID page.
Do you have any other butterfly websites?
- Yes, I do! I am revising them but you may want to visit one, My Butterfly Guide.
My caterpillar is throwing up. Is this normal?
- No, Monarchs should NOT throw up! If the 'vomit' is runny, then you know that there is definitely a problem since Monarch frass (poop) should be firm little pellets. The vomit or diarrhea can indicate several things: the food/leaves you are giving could be poisoned with perhaps a systemic insecticide, the caterpillar could be stressed (was it exposed to extreme heat conditions then brought into an air conditioned room?), or it could even have an infection (visit Black Death).
My caterpillars started twitching and jerking their heads around then died. What happened?
- Whenever a caterpillar does that weird twitching, dance thing, usually what follows is vomiting. This is NOT a good sign but means that the Milkweed it ate was poisoned! If you buy Milkweed from a store, chances are it has been treated with a systemic insecticide and this type of treatment means that the poisons are absorbed by the plant from the roots on up. It will take at least two months before the plant will be safe to feed your caterpillars. You MAY be able to save your caterpillar if you see that weird jiggling dance if you can feed it untreated leaves but it is not likely that the caterpillar will survive. Bummer.
How do I euthanize a butterfly or caterpillar?
- There are several ways to euthanize a sick insect. It depends upon what YOU feel most comfortable doing. One method is called the 'killing jar' where a jar with a lid is used. Soak a cotton ball with nail polish remover containing acetone and drop both the cotton ball and insect into the jar. Seal the jar and within minutes, the insect will be euthanized. Another is the 'freezing' method, my preference. Place the insect into a baggy, seal the baggy, and place it into the freezer overnight. The freezing temperatures will slow down the insect's body functions and you can then dispose of the baggy the following day.
My chrysalis fell. Is it dead? Should I try to hang it back up? What can I do?
- First, answer this question: Do you see any liquid coming out of the chrysalis? If the answer is yes, then unfortunately, your butterfly is dead. If no liquid is coming out, then your butterfly is probably okay. You can do several things: you can leave the pupa on the ground (bottom of the habitat or whatever you are using to raise your butterflies), you can make a 'cushion' or pillow of tissues or even use a little towel to nestle the chrysalis in, you can try to carefully use a thread to tie the cremaster (that little black thingie that attaches the pupa to whatever it was hanging from), or even try to use a hot glue gun to re-attach the cremaster to whatever it was hanging on. Personally? I just leave the chrysalis alone and make sure that there's a stick nearby so that when the butterfly does eclose (come out of the chrysalis) it has a way to climb up and dry its wings and I make sure the pupa is on top of some tissue. Butterflies are pretty resilient creatures.
My caterpillars keep dying! I have sterilized everything and kept things clean. What am I doing wrong?
- Don't be so hard on yourself. Keep in mind that the VAST majority of eggs laid do NOT make it to become adult butterflies! If even 10% of the eggs that one mama Monarch lays makes it to the adult butterfly stage then that would be an outstanding statistic. Predation, illness, parasitoids, parasites, and other causes are often the causes of death. Many larvae die in the very earliest instars. Just continue to be diligent in your cleanliness.
I had all these caterpillars on my Milkweed a little while ago. When I went to look again, they were all gone. What happened?
- If you had seen large caterpillars then chances are, they were getting ready to pupate! Generally speaking, caterpillars will often take off and leave their host plants when they're ready to pupate as they want to find a safe spot for the ten days or so that they will spend in their next life-cycle stage. Don't be surprised to find a lovely pupa in the most unusual place! Now, if your caterpillars were small, there are several possibilities for their disappearance. They may be hiding around the plant. A spider may have taken off with one for its dinner. The little caterpillar could have contracted a virus or bacteria and simply died, it could have been eaten by a lizard, or if you live where there are toads or frogs, they could also be the culprit. Younger instars tend to die early so it isn't surprising to have them 'disappear.'
I want to keep track of what I raise. Is there an easy way to record the data?
- The Monarch Larva Monitoring Project led by Dr. Karen Oberhauser at the University of Minnesota is an oustanding resource and their website has a superb on-line data entry system for keeping track of your Monarch collecting and rearing! What is even better is that your data is used to help with research on these magnificent butterflies so everyone wins.
Do caterpillars need water to drink? How about the pupa (chrysalis)?
- No, caterpillars do not need to drink water as they get all the moisture they need from the fresh leaves they consume. The pupae do not need to be watered either. Moisture is NOT a good thing as it can lead to problems with molds, bacterial, and viral infections especially when you add heat to the mix. Keeping the environment clean and dry is going to be key to raising healthy butterflies.
Are Monarch caterpillars carnivorous? Are Monarch caterpillars cannibalistic?
- Although Monarchs are not truly carnivorous they may eat one another on occasion during the larval stage. More than likely, the eating occurs by accident and happens when a larger caterpillar mistakenly munches a smaller one simply because the little one is on the leaf the big guy is eating! It's a case of being in the wrong place at the wrong time.
My butterfly is stuck in its chrysalis. Should I help it?
- When Monarchs get 'stuck' in their chrysalis, do not try to help them. It is a bad sign and is probably a case of the nasty Oe spore parasitoid. Read the section, please. Euthanize the butterfly as quickly as possible and be sure to sanitize EVERYTHING, including your hands, so as not to spread the disease.
My butterfly has a bent wing. Should I try to fix it? Is there a video or something on how to do this?
- There are a number of reasons why the butterfly ended up with a 'bent' wing and so it is hard to say just how it happened: perhaps there was an injury done to the larva, maybe the Oe spore caused the butterfly wing scales to form in a haphazard manner, …Although you can find videos on-line showing how to 'correct' a bent wing using glue and another butterfly's wing, I don't believe it is a good idea if you aren't positive that the specimen you have is not one that is disease-free.
Does the Tachinid Fly lay its eggs on the leaves of the Milkweed? Can the caterpillar eat the fly eggs?
- The type of Tachinid Fly that parasitizes the Monarch butterfly is specific to the Monarch and must oviposit (lay) its egg onto its host. This means the fly must lay the egg(s) onto the Monarch directly. It injects the egg onto the Monarch caterpillar OR egg. The fly doesn't lay eggs onto Milkweed leaves. So, you don't have to worry that your Milkweed leaves will have fly eggs on them that the caterpillars will eat.